California’s five-year drought is changing our take on rainfall in cities, recasting it from a threat to a resource. “For so long, stormwater was simply a nuisance,” said Keith Lichten of the San Francisco Bay Regional Water Quality Control Board. “We needed to get it out of the way as quickly as possible to protect structures.” But stormwater can also be an asset. Instead of directing it into gutters and straight down storm drains, we can capture and clean it in rain gardens and other planted areas.